[flexiglass] Ignore window insets in scene container root, and adjust Shade/QS layouts accordingly

Scene Container root no longer applies window insets to children, and leaves it up to individual scenes to consume them. Landscape shade work should be considered done after this lands.

Bug: 324113487
Bug: 335828150
Test: Visually verified legacy windowInsets are unchanged
Test: Visually verified portrait mode single shade and split shade is unchanged
Test: Visually verified landscape mode single shade now correctly adjusts to window insets
Flag: ACONFIG com.android.systemui.scene_container DEVELOPMENT
Change-Id: Idfc21d2b6ad31b69c50582079b61fa2e4adf2886